Device for decapping and recapping sample tubes

ABSTRACT

A decapping/recapping device for removing closures from sample tubes and for reclosing sample tubes with the same closures is presented. The device comprises individual closure holders, each holder comprising a passive closure gripper for holding a closure, at least one actuator for actuating the passive closure gripper when removing a closure from a tube or reclosing a tube with its respective closure and at least one tube gripper cooperating with the at least one actuator for biasing a tube and its closure away from each other when removing the closure and for biasing the tube and its closure towards each other when reclosing the tube. One actuator is coupled to one passive closure gripper of a closure holder when removing a closure from a tube or when reclosing a tube with its respective closure and is decoupled from a passive closure gripper when the closure holder is holding a closure.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of EP 11179615.6 filed Jun. 20, 2011,which is hereby incorporated by reference.

BACKGROUND

The present disclosure generally relates to in vitro diagnostics devicesfor automatically removing closures from sample tubes and, inparticular, to a decapping/recapping device for removing closures fromsample tubes and for reclosing the same tubes with the same respectiveclosures. The present disclosure also refers to a pipetting system andto an analytical system comprising the decapping/recapping device.

Coming from diverse healthcare facilities, biological samples such asblood samples usually arrive in the laboratories in different kinds ofsample tubes with various closures. These are called primary sampletubes because they are used to collect the samples, e.g., byvenipuncture.

There are instruments, which may process primary sample tubes withoutthe need to remove the closure, i.e., by accessing the sample containedin the primary tube by piercing the closure with, for example, apipetting needle. Not all closures are however suitable for thisprocedure and not all types of instruments and/or analysis allow thistype of procedure. Some types of instruments and/or analysis require theprimary tubes to be opened before samples are pretreated and/oranalyzed. Therefore, such instruments should have an automatic decapperto automatically remove the closure from a primary tube.

Automating decapping of test tubes is complicated by the variety ofavailable test tubes, which may vary in diameter, height, and,especially, the variety of available closures. Some closures have, forexample, a thread for screwing on primary tubes. Another type of closureis a rubber stopper or cap, which may be removed by a pulling motion.The closures may also differ in their composition. They may be made ofrubber, plastic, etc.

Decapping devices that can decap, i.e., remove closures from, all ormost of these types of primary tubes have been developed and areavailable on the market. However, in decapping the tubes, care must betaken not to break the tubes, generally made from glass or plastic, andnot to spill any of the sample. There is a further constraint thatspills of the sample and any vapors should not be transmitted to othertubes in the instrument which would cause cross-contamination andinterfere with the testing and analysis of the samples. Moreoverbio-hazard is also an issue as samples are potentially infectious. Thustubes and closures have to be processed and/or disposed securely.

Once a primary tube has been opened and once a volume of sample has beenwithdrawn from the tube for processing, it is often desirable to reclosethe primary tube, for example, for safety reasons as mentioned aboveand, in any case, if samples have to be stored for a longer period oftime in the event that a further analysis is later required.

One approach is to dispose the original closure after opening theprimary tube and to reclose the primary tube with another standard oruniversal closure. This has the main advantage to make the various stepsof opening, pipetting and reclosing more independent from each other. Inthis way, a primary tube can be opened by a decapping device, moved to awork cell where samples are pipetted and processed and then moved to arecapping device where they are reclosed with a new closure, wherein theprocess can start over again for another tube before the processing ofthe previous tube is completed. Another advantage is that recapping ismade easier because standard closures of one type are used and if tubesneed to be re-opened, decapping is also easier. A disadvantage, however,is that a new closure is introduced for each primary tube, thusincreasing processing costs and waste volumes as well as the complexityof the recapping device, since the delivery of a new closure to therecapping device for each tube is needed.

Ideally, the same closure that is removed from a primary tube is used toreclose the same tube. Decapping/recapping devices able to remove aclosure of any type and reclose the tube with the same closure after avolume of sample has been withdrawn are also known. This type of devicehowever has the disadvantage that sample processing throughput can becompromised since all steps of opening, pipetting, closing and moving atube need to be completed before the process can be repeated for anotherprimary tube.

Therefore there is a need for a decapping/recapping device for removingclosures from sample tubes and for reclosing the same tubes with thesame respective closures in order to increase processing throughput ofsample tubes and decrease processing costs.

SUMMARY

According to the present disclosure, a decapping/recapping device forremoving closures from sample tubes and for reclosing the sample tubeswith the same respective closures is presented. The decapping/recappingdevice comprises a plurality of individual closure holders, where eachindividual closure comprising a passive closure gripper for holding aclosure and at least one actuator for actuating the passive closuregripper when removing a closure from a tube or reclosing a tube with itsrespective closure. The at least one actuator is coupled to the passiveclosure gripper of an individual closure holder when removing a closurefrom a tube or when reclosing a tube with its respective closure and isdecoupled from the passive closure gripper when the individual closureholder is holding a closure. The decapping/recapping device furthercomprises at least one tube gripper cooperating with the at least oneactuator for biasing a tube and its closure away from each other whenremoving the closure and for biasing the tube and its closure towardseach other when reclosing the tube.

In accordance with one embodiment of the present disclosure, a pipettingsystem comprising the decapping/recapping device is presented.

In accordance with another embodiment of the present disclosure, ananalytical system comprising the decapping/recapping device ispresented.

Accordingly, it is a feature of the embodiments of the presentdisclosure to have a decapping/recapping device for removing closuresfrom sample tubes and for reclosing the same tubes with the samerespective closures in order to increase processing throughput of sampletubes and decrease processing costs. Other features of the embodimentsof the present disclosure will be apparent in light of the descriptionof the disclosure embodied herein.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

The following detailed description of specific embodiments of thepresent disclosure can be best understood when read in conjunction withthe following drawings, where like structure is indicated with likereference numerals and in which:

FIG. 1 a illustrates a perspective view of a pipetting system comprisinga decapping/recapping device according to an embodiment of the presentdisclosure.

FIG. 1 b illustrates a magnification of the decapping/recapping deviceshown in FIG. 1 a wherein some parts have been removed for clarityaccording to an embodiment of the present disclosure.

FIG. 2 a illustrates one of the plurality of closure holders asillustrated in FIGS. 1 a and 1 b according to an embodiment of thepresent disclosure.

FIG. 2 b illustrates the closure holder of FIG. 2 a wherein part of thehousing has been removed for making some of the inner components visibleaccording to an embodiment of the present disclosure.

FIG. 2 c provides further insight to the working principle of theclosure holder of FIGS. 2 a and 2 b according to an embodiment of thepresent disclosure.

FIG. 2 d illustrates a bottom view of the closure holder of FIG. 2 aaccording to an embodiment of the present disclosure.

FIG. 3 illustrates an actuator with some parts removed to reveal someinner components according to an embodiment of the present disclosure.

FIG. 4 a illustrates a carousel-like rotor carrying a plurality ofclosure holders as illustrated in FIGS. 1 a and 1 b according to anembodiment of the present disclosure.

FIG. 4 b illustrates a partially cut view of the carousel of FIG. 4 aaccording to an embodiment of the present disclosure.

FIG. 5 illustrates a top view of the system of FIG. 1 a wherein someparts have been removed for clarity according to an embodiment of thepresent disclosure.

FIGS. 6 a-b illustrate in perspective from top and bottom respectivelyhow an actuator and a passive closure gripper are being engaged (someparts removed for clarity) according to an embodiment of the presentdisclosure.

FIG. 6 c illustrates the actuator and passive closure gripper of FIGS. 6a and 6 b already engaged (some parts removed for clarity) according toan embodiment of the present disclosure.

FIG. 7 illustrates a tube gripper in more detail according to anembodiment of the present disclosure.

FIG. 8 a illustrates a perspective view of a decapping/recapping deviceaccording to another embodiment of the present disclosure.

FIG. 8 b illustrates a pipetting system comprising thedecapping/recapping device of FIG. 8 a according to an embodiment of thepresent disclosure.

FIG. 8 c illustrates the pipetting system of FIG. 8 b from anotherperspective according to an embodiment of the present disclosure.

FIG. 8 d illustrates a top view of the same pipetting system of FIGS. 8b and 8 c according to an embodiment of the present disclosure.

FIG. 9 illustrates a top view of a decapping/recapping device accordingto another embodiment of the present disclosure.

FIG. 10 illustrates schematically a system for processing sample tubescomprising a plurality of work cells and a plurality of pipettingsystems according to an embodiment of the present disclosure.

DETAILED DESCRIPTION

In the following detailed description of the embodiments, reference ismade to the accompanying drawings that form a part hereof, and in whichare shown by way of illustration, and not by way of limitation, specificembodiments in which the disclosure may be practiced. It is to beunderstood that other embodiments may be utilized and that logical,mechanical and electrical changes may be made without departing from thespirit and scope of the present disclosure.

A “sample tube”, herein interchangeably referred to also as “tube”, canbe either a sample collection test tube, also called “primary tube”,which can be used to receive a sample such as a blood sample from apatient and to transport the sample contained therein to an analyticallaboratory for diagnostics purposes, or a “secondary tube”, which may beused to receive an aliquot of sample from a primary tube. A primarysample tube is typically made of glass or plastics, has a closed end andan open end closed by a closure, which may be of different materials,assume different shapes and colors, typically associated with the typeof tube, i.e. the type of sample therein or the type of conditions thesample therein is subjected to. There are for example tubes containingan anticoagulant or a coagulation inducing agent, there are tubescontaining gels facilitating the separation of plasma, etc. Differenttypes of primary tubes are often just the result of customization ofdifferent primary tube manufacturers. Most often they reflect the typeof sample and or analysis they are destined to. Primary tubes can bedifferent size, i.e., of different diameter and/or different height forreceiving different amounts of samples. A single laboratory, andtypically a single instrument, can therefore be required to be able tohandle different types of primary tubes with possibly different types ofclosures. A secondary tube can typically be made of plastics and mayhave a lower degree of variation of size and type with respect toprimary tubes. In particular, secondary tubes may be smaller thanprimary tubes and be designed to be closed with one type or similartypes of closure, e.g. a screw type.

The term “closure” is herein used to indicate any type of cap,comprising screw-type caps and rubber stoppers, which can be openedand/or closed by a pulling/pushing and/or screwing motion respectively.

A “decapping device” can be a device capable of automatically openingsample tubes of the same or different types by removing closures of thesame or different types from their respective tubes.

A “decapping/recapping device” can be a device capable of automaticallyopening sample tubes of the same or different types by removing closuresof the same or different types from their respective tubes and can becapable of automatically reclosing sample tubes with the same respectiveclosures, which were removed from those tubes. Thus, adecapping/recapping device can be a decapping device, which additionallyis adapted to reclose sample tubes with the same respective closures. Adecapping/recapping device may also be used as a decapping device only.Therefore, unless otherwise specified, the general term “device” ishereafter used to indicate either or both a decapping device and adecapping/recapping device.

A device can comprise a plurality of individual closure holders, eachcomprising a passive closure gripper for holding a closure. A “closureholder” can be a device capable of holding a closure for a period oftime between decapping, i.e. removal of that closure from a sample tube,and either disposal of that closure or recapping, i.e. reclosing of thesame sample tube with that same respective closure. Each closure holdercan comprise a passive closure gripper, a function of which is tosecurely hold a closure by a passive frictional pressure applied on theouter surface of a closure, preventing the closure to move and/or tofall. “Passive” can mean that there is a force or energy transferbetween the passive closure gripper and other parts of the device,specifically an actuator, only when removing a closure from a sampletube or disposing a closure or reclosing a sample tube with itsrespective closure and there is no force or energy transfer between thepassive closure gripper and the actuator during the period of timebetween decapping and disposal or recapping, the force required forholding the closure during this period of time being resilient andinternal to the passive closure gripper itself. Thus, a closure grippercan be passive in the sense that it needs to be coupled with an actuatorwhen decapping or recapping has to take place but cannot perform suchactions without being coupled to an actuator.

An “actuator” can be a device for actuating, i.e. transferring force orenergy to the passive closure gripper when removing a closure from atube or reclosing a tube with its respective closure. The actuator canbe coupled to a passive closure gripper of a closure holder when aclosure has to be removed from a tube or when a tube has to be disposedor reclosed with its respective closure and being decoupled from apassive closure gripper when the closure holder is holding a closure.According to one embodiment, the force can be an axial force,transferred to the passive closure gripper by applying a positive ornegative pressure, e.g. by pushing or pulling a passive element of thepassive closure gripper. The force may also or in addition berotational, transferred to the passive closure gripper by coupling torotational drive means. The force may be however also induced, i.e.without physical contact, e.g. magnetic.

“Coupled to” or “in coupling connection”, when referring to therelationship between an actuator and a passive closure gripper, can meanthat an actuator is engaged with a passive closure gripper and atransfer of force from the actuator to the passive closure gripper isenabled. Engagement may occur by physical contact and/or alignment.“Decoupled from” can mean that the actuator and the passive closuregripper are disengaged, i.e. physically separated from each other ormisaligned. Alternatively, the actuator and the passive closure grippermay still be in physical contact or aligned but the transfer of forcefrom the actuator to the passive closure gripper is disabled, meaningthat there is no force or energy transfer from the actuator to thepassive closure gripper.

Therefore, it is thus possible to couple a plurality of closure holdersto one or more actuators. According to one embodiment, one or moreactuators are fixed within the device while a plurality of closureholders are movable with respect to the fixed actuators such as to be inturn coupled to one or more actuators. Of course the opposite can alsobe possible, wherein a plurality of closure holders is fixed and one ormore actuators are movable with respect to the fixed closure holders.

The device can further comprise at least one tube gripper cooperatingwith the at least one actuator for biasing a tube and its closure awayfrom each other when removing the closure and for biasing the tube andits closure towards each other when reclosing the tube. According to oneembodiment, the at least one tube gripper can be aligned with the atleast one actuator. If there are a plurality of actuators and aplurality of tube grippers, two or more tube grippers may be alignedwith a respective number of actuators. According to one embodiment, thetube gripper can lift and hold a tube with respect to a closure holdercoupled to an actuator wherein the actuator cooperates with the tubegripper to remove a closure from the sample tube or reclose the tubewith its original closure held by the closure holder. It is however alsopossible to adapt the device such that the tube gripper can hold asample tube without lifting it while the closure holder and/or theactuator are moved with respect to the tube gripper. Alternatively, thetube gripper and the closure holder and/or the actuator can move withrespect to each other.

According to one embodiment, the closure gripper can comprise a grippingtool and a pre-tensioning member connected to the gripping tool, such asa spring, pre-tensioning the gripping tool with respect to the closureholder in one pivoting direction (closing direction) for exercising apressure on the sides of a closure symmetrically arranged in between,wherein the pressure is releasable upon coupling the actuator to thepassive closure gripper by a force applied by the actuator on thepre-tensioning member. The closure is preferably held hanging by thegripping tool without touching other surfaces or parts of the deviceuntil disposed or returned to its respective sample tube.

According to one embodiment, the gripping tool can comprise a pluralityof jaws symmetrically arranged with respect to a central vertical axisof the closure holder, each jaw comprising a friction surface,preferably a plurality of protrusions, e.g. conical protrusions,preferably arranged in a two-dimensional array, the jaws cooperatingwith each other to grip and hold a closure.

This embodiment can particularly be advantageous for removing andholding closures of variable shape and material and also for reclosingsample tubes with the closures since the maximum gripping power with theminimum contact surface can be achieved. In this way, a closure can beheld firmly without falling during holding or sliding through the jawsduring decapping or recapping. Moreover, asymmetrical deformations ofthe closure are prevented for smooth and efficient decapping andrecapping. Also, only a minimum contact between the gripper and theouter sides of the closure takes place, thus minimizing the risk ofcross-contamination from one closure to the next closure due to possiblesample traces present on the inside and/or bottom surface of theclosure. According to one embodiment, each jaw can pivot about ahorizontal jaw axis by varying its angle relative to the centralvertical axis of the closure holder. This can enable the jaws to adaptto different inclinations of the sides of the closure without losinggripping surface and power.

According to one embodiment, the closure holder can comprise a passiveclosure push element, independent from the gripping tool, comprising aresilient member, e.g. a spring, for exercising a push force on theclosure in a vertical direction when the pressure of the gripping toolis released. The push element may be advantageously mounted above thegripping tool, e.g. the jaws. In this way, upon inserting a closure inthe space between the gripping tool, e.g. by lifting a closed sampletube towards the closure holder, the push element can be pushed upwardsby the closure and the resilient member can be tensioned. The resilientforce of the resilient member is chosen such that it is weaker than theresilient force of the pre-tensioning member. Therefore as long as theclosure remains tight held by the gripping tool, during the holdingperiod, the push element is limited to exercise only a pressure on thetop of the closure without additional effects. In the event that aclosure is returned to a sample tube, during reclosing, the effect ofthe push element is also marginal, even though it may contribute to theclosing. In the event that a closure needs to be disposed by releasingthe pressure of the gripping tool, e.g. by opening the jaws uponcoupling with the actuator, and allowing the closure to fall by gravity,it may occasionally happen that a closure remains stuck or that aclosure gripper remains jammed. The push element can thus beadvantageously designed for contributing to expel the closure by pushingit out from the closure holder. The push element may be however designedfor exercising an additional effect, especially on certain types ofclosures such as rubber stoppers having a concave shape, i.e. a cavity,on the top of the closure. In this case, if the push element is shapedsuch as to fit at least in part in the cavity of the closure,asymmetrical deformation and/or tilting of the closure may be preventedwhen gripping the closure by the gripping tool. This can enable properdecapping and recapping of the sample tube.

According to one embodiment, the closure gripper can rotate about thecentral vertical axis of the closure holder upon coupling the actuatorto the passive closure gripper. The actuator can comprise aclosure-gripper drive for rotating the closure gripper. Rotation may benecessary for threaded screwable closures. Rotation may however beadvantageous for other types of closures as well, not necessarilyrequiring screwing. According to one embodiment, the closure gripper isrotated thus rotating the closure with respect to the tube, while thetube gripper maintains the tube stationary. Alternatively, it ispossible to rotate the tube while maintaining the closure stationarybetween the gripping tool.

According to one embodiment, the device can comprise a closure-holderdrive for sequentially and/or repeatedly bringing the plurality ofclosure holders in coupling connection with one or more actuators and/ora tube conveyor for bringing one tube at a time in gripping alignmentwith a tube gripper.

According to one embodiment, the device can comprise a decapping stationwhere a decapping actuator can be aligned to a decapping tube gripper, arecapping station where a recapping actuator can be aligned to arecapping tube gripper, wherein a closure holder and a tube are movablefrom the decapping station where the decapping actuator and thedecapping tube gripper cooperate with the closure gripper to remove aclosure from the tube, to the recapping station wherein the recappingactuator and the recapping tube gripper cooperate with the same closuregripper holding the closure to reclose the same tube with the sameclosure. The decapping and recapping actuators may be structurallyidentical but have different dedicated functions, i.e. for decapping andrecapping respectively. They can be coupled to and actuate the samepassive closure gripper but may be more specifically adapted for eitherdecapping or recapping, for example by setting the closure-gripper driveto rotate a passive closure gripper clockwise or counterclockwise.

According to one embodiment, the plurality of individual closure holderscan be arranged on a translatable linear array or a rotatable rotor-likearray or a robotic arm-like transportation unit, with possible randomaccess to any actuator. According to one embodiment, the plurality ofclosure holders can be symmetrically arranged on a carousel-type rotorcomprising a plate or branches rotatable about a central rotor axis. Theclosure-holder drive may comprise in this case a motor driving thecarousel in a controlled manner about its axis via e.g. a belt-pulley orgear-like mechanism or induction like mechanism. The rotor may comprisea position sensor for controlling and/or monitoring the angle ofrotation such as to facilitate a proper alignment between actuator andclosure holder at every rotation.

Sample tubes may be moved with respect to the device, particularly withrespect to a decapping and/or recapping station, with a tube conveyor.Sample tubes can be carried on tube carriers, which may be either singletube carrier, so called “Pucks”, or multi-tube carriers, so called “tuberacks”, comprising a plurality of tube receptacles for receiving e.g. upto 5 tubes or more and typically adapted to receive different types oftubes, i.e. of variable diameter and height. The tube conveyor maytherefore comprise a transportation unit, such as a transportation bandor guide rail driven by a motor and arranged such that a tube carrier ismoved stepwise for bringing a tube at a time in alignment with adecapping and/or recapping station. The transportation unit may howeverbe adapted to move tubes on special tube carriers customized accordingto the requirements of a decapping/recapping device and confined in theworking area of the decapping/recapping device. In this case, areformatting device for transferring sample tubes from pucks and/or tuberacks to these special carriers and vice versa may be operativelycoupled to the decapping/recapping device. Closure-holder drive meansand tube conveyor can be synchronized to bring a tube and its closure tothe same recapping station after the closure has been removed at adecapping station.

According to one embodiment, the device can comprise a heightdetermining detector cooperating with the tube gripper for determiningthe height at which a tube is to be lifted when removing a closure froma tube or reclosing the tube with its closure. The height determiningdetector may be for example a code reader for reading a code placed on atube or a tube carrier and identifying the type of tube or rack, e.g. abar code reader or an RFID reader. The height determining detector mayalso be optical, comprising e.g. a camera-type detector or other lightsensor adapted to measure geometrical parameter of the sample tubesand/or closures, particularly the height and/or the diameter of the tubeand/or the size and shape or color of the closure. The heightdetermining detector may be set up to send a signal to the tube grippereither directly or via a control unit. In this way the variability ofthe sample tube type is taken into consideration and each sample tube islifted according to its respective geometric parameters, enabling itsclosure to be gripped and removed or enabling the tube to be reclosedwith its closure held by the closure holder.

According to one embodiment, the tube gripper can comprise a first tubegripping tool and a second tube gripping tool. The first tube grippingtool can be biasable with respect to the second gripping tool and cancooperate with the second tube gripping tool such as the first tubegripping tool grips and can lift a tube from a tube carrier before thesecond gripping tool grips and holds securely the tube with a force anda surface of contact which are greater than the force and surface ofcontact of the first gripping tool respectively. This double grippingmechanism enables gripping the side wall of a tube in the often narrowspace between a tube carrier and a closure with a smaller gripper meansand to lift it to a height wherein a larger and stronger gripping toolcan grip a longer portion of the side wall for a more secure grip.

According to one embodiment, the device can comprise an error detectorcomprising a sensor and a controller to determine whether a closure hasbeen removed and/or a tube has been reclosed with its respective closureand/or to prevent a tube from being reclosed with a non-respectiveclosure. The error detector may be the same, similar or share componentswith the height determining detector. The error detector may comprise anoptical detector, e.g. a camera-type detector or other light sensoradapted to measure geometrical parameters and/or the presence or absenceof a closure on a respective sample tube and/or in a closure holder. Theerror detector may be set up to compare a closed sample tube beforedecapping and after recapping. In the event of any error in thedecapping/recapping process, it may emit a warning or alert signal tointerrupt the decapping/recapping process and/or to instruct the deviceto dispose a closure which failed to reclose a sample tube before it isaccidentally brought in contact with other closures or other sampletubes. Further, it may send instructions to process sample tubes leftopen or tubes, which failed to be opened, differently from the rest ofthe tubes.

According to one embodiment the device can comprise a waste stationwhere a waste actuator is aligned to a waste compartment. A closureholder can move from a decapping station where a decapping actuator anda decapping tube gripper cooperate with the closure gripper to remove aclosure from the tube to the waste station. The waste actuatorcooperates with the same closure gripper holding the closure to disposethe closure into the waste compartment. Alternatively or in addition,the closure holder may move from a recapping station where a recappingactuator and a recapping tube gripper cooperate with the closure gripperto reclose a tube with its respective closure, to the waste station.This may happen in the event that an error occurred when trying toreclose the tube and the closure remained in the closure holder. Inorder to free the closure holder and make it available for anotherclosure from another tube and/or to prevent that a different tube isclosed with a closure that does not belong to that tube, the closure istherefore disposed at the waste station before the closure holder isreturned to a decapping or recapping station.

According to one embodiment, the device can comprise at least onedecapping station and at least one waste station. According to oneembodiment, the device can comprise at least one decapping station andat least one recapping station. According to one embodiment, the devicecan comprise at least one decapping station, at least one recappingstation and at least one waste station. In all of these embodiments, aplurality of closure holders can move from one station to anotherstation by being coupled to a respective actuator. It is howeverpossible that a closure holder only passes by a station without beingcoupled to an actuator. This may be for example the case if the closureholder is moved from a decapping station to a recapping station via awaste station. As there is no intention to dispose the closure becauseit is intended to reclose its respective tube at the recapping station,there will be no coupling between the actuator and the passive closuregripper at the waste station unless an error in the intended process wasdetected.

A pipetting system for withdrawing volumes of samples from sample tubesand/or dispensing a volume of another liquid, such as a reagent ordiluting buffer, into a sample tube or reaction vessel can comprise adecapping/recapping device and a pipetting unit adapted, e.g.synchronized with the decapping/recapping device, to withdraw a volumeof sample or dispense a volume of liquid in the time frame between theopening of a tube and the reclosing of the tube with the same closure.The pipetting unit may comprise one or more reusable washable needle,e.g. a steel needle, or use disposable pipette tips. The pipetting unitmay be mounted to a transfer head that can be moved in one or twodirections of travel in a plane, e.g. with guiding rails and a thirddirection of travel orthogonal to the plane, e.g. with a spindle drive.

The pipetting system can comprise a pipetting station where thepipetting unit, such as the pipette tip or needle, can be aligned withan open tube between decapping and recapping. The pipetting station maycomprise a pipetting tube gripper similar or identical to a decapping orrecapping tube gripper for lifting the tube such as access of thepipetting unit to the sample therein is facilitated. According to oneembodiment, the pipetting station can be located between the decappingand recapping station in a path of travel of a tube carrier between thedecapping station and the recapping station.

In a system that operates with single tube carriers, the decappingstation and the reacapping station can be located at a distance fromeach other, which can correspond to the distance between the center of atube and the center of a second apart tube in a series of tubes whosecarriers are adjacent to each other. The pipetting station can belocated in the middle, i.e. in correspondence to a tube in between. Inone embodiment, the number of closure holders can be three. In this waya cycle may be defined wherein in a same fixed time frame, three tubesmay be processed and three different steps may be performed. A firsttube may be opened while a volume of sample can be withdrawn from or avolume of liquid is being dispensed into a second tube previously openedwhile a third tube, from or into which a volume of liquid has beenpreviously withdrawn or a volume of liquid has been previouslydispensed, can be reclosed with the same closure that in the same timeframe has been transported by one of the closure holders from thedecapping station to the recapping station. The cycle can then startover again.

In a system that operates with tube racks, the decapping station and thereacapping station can be located at a distance from each other, whichcan correspond to the distance between the center of a tube in the firstreceptacle of a first tube rack and the center of a first tube in thefirst receptacle of a second tube rack adjacent to the first tube rack.This can be advantageous if the distance between the centers of twotubes on the same rack is not the same as the distance between thecenter of the last tube and the center of the first tube respectively onadjacent racks. The pipetting station can also be located approximatelyin the middle, i.e. between decapping station and recapping station incorrespondence to one of the intermediate tube positions. In oneembodiment, if the tube racks comprising five receptacles for receivinga respective number of tubes, the number of closure holders can be six.In this way a cycle may be defined wherein three tubes may be processedand three different steps may be performed in a same fixed time frame. Atube on a rack, e.g. the first tube, may be opened while a volume ofliquid is being pipetted from or into one of the tubes in a precedingrack previously opened while another tube, e.g. the first tube on thepreceding rack, from which or into which a volume of sample has beenpreviously pipetted, can be reclosed with the same closure that in thesame time frame has been transported stepwise by one of the six closureholders from the decapping station to the recapping station.

A method of pipetting samples from sample tubes with the pipettingsystem can comprise opening a tube by removing the closure from the tubeat a decapping station, withdrawing a volume of sample from the opentube and/or dispensing a volume of liquid into the open tube by thepipetting unit at a pipetting station and reclosing the tube with thesame closure at a recapping station.

According to certain embodiments, the method can comprises performing inthe same time frame opening a first tube by removing a first closurefrom that first tube at a decapping station, closing a second tube witha second closure removed from that same second tube at a recappingstation, and withdrawing a volume of sample from an opened tube ordispensing a volume of liquid into an opened tube at a pipettingstation, disposing a closure at a waste station.

The term “time frame” is here used to indicate a predetermined timewindow, e.g. in the range of a few seconds, e.g. 1 to 10 seconds, whichdefines a cycle during which at least two of the above mentioned stepstake place either sequentially or in parallel or in overlap.

According to one embodiment, the method can comprise moving a tube andits closure independently from each other but in a synchronized mannerfrom a decapping station, where the closure is removed, to a recappingstation, where the tube is reclosed with the same closure, and pipettinga volume of sample from the opened tube and/or dispensing a volume ofliquid into the opened tube in the time frame between decapping andrecapping. According to certain embodiments, closures can be moved froma decapping station to a recapping station following a path of travelwhich does not overlap with the path of travel of the sample tubesexcept at the decapping station and recapping station. Analogously,according to certain embodiments, the pipetting unit can move followinga path of travel, which does not overlap with the path of travel ofopened sample tubes, except at the pipetting station. In this way, itcan be prevented that samples in opened tubes are contaminated byeventual droppings from the closures while being held by a closureholder or from the pipetting unit.

Alternatively or in addition, the device may comprise a plate or shieldlocated underneath the path of travel of the closure holders to protectother parts of the device from eventual droppings from closures held bythe closure holders. Also, when cross-contamination is of particularconcern such as when samples are used for nucleic acid amplification,other or additional measures may be implemented such as separating partsof the device in different compartments or enclosing the device ordevice parts in an aerosol free compartment such as a hood.

An analytical system for determining at least one sample parameter of asample contained in a sample tube can comprise a decapping/recappingdevice and an analytical unit for determining the at least one sampleparameter, such as a physical, chemical or biological parameter of asample contained in a sample tube, normally without the addition of areagent, in the time frame between the opening of a tube and thereclosing of the tube with the same closure. The analytical unit may befor example a sensor for determining a physical parameter of the sample,such as pH, temperature, colour, turbidity, viscosity, or quantity, e.g.volume, or liquid level of the sample within the tube. It may comprisefor example an optical detector or a probe to be dipped at leastpartially into the sample. It may e.g. determine chemical or biologicalparameters such as analytes contained in the sample by photometricmeasurement or other physical techniques making use for example of ionselective electrodes or reagent coated strips subject to colour change,etc. The analytical system may further comprise a pipetting unit asabove described.

A method of determining at least one sample parameter of a samplecontained in a sample tube with the analytical system can comprisesopening a tube by removing the closure from the tube at a decappingstation, determining at least one sample parameter by the analyticalunit and reclosing the tube with the same closure at a recappingstation.

The same analytical unit may of course determine at least one sampleparameter without the need to open a tube, e.g. before decapping and/orafter recapping, especially if an optical detector is used.

A system for processing sample tubes comprising biological samples cancomprise a plurality of work cells for processing samples and optionallyat least one transportation unit to transport sample tubes from one workcell to at least another work cell. The system can further comprises apipetting system in correspondence to at least one work cell forwithdrawing a volume of sample from a sample tube to be processed by thework cell or dispensing a volume of liquid into the sample tube. Thepipetting system can comprise a decapping/recapping device for removinga closure from a sample tube when a sample needs to be withdrawn or aliquid needs to be dispensed and for reclosing the sample tube before itis transported to another work cell.

A work cell can be either a stand-alone apparatus or a module within alarger instrument assisting users with the detection, e.g. qualitativeand/or quantitative evaluation of samples for diagnostic purpose, orwith the sorting and/or preparation of samples before detection, or withthe storing and/or disposal of samples after detection. A work cell maybe related to analytical and/or to pre-analytical and/or topost-analytical sample processing steps. Work-cells may connected toeach other and depend at least in part on each other, e.g. each carryingout a dedicated task of a sample processing work-flow, which may be aprerequisite before proceeding to the next work-cell. Alternatively,work cells may work independently from each other, e.g. each carryingout a separate task, e.g. a different type of analysis on the samesample.

An analytical work cell can be either a stand-alone apparatus or modulewithin a larger instrument assisting users with the detection, e.g.qualitative and/or quantitative evaluation of samples for diagnosticpurpose. It may comprise a process and detection system whose workflowcan be optimized for certain types of analysis. Examples of such workcells are clinical chemistry analyzers, coagulation chemistry analyzers,immunochemistry analyzers, urine analyzers, used to detect the result ofchemical or biological reactions or to monitor the progress of chemicalor biological reactions. An analytical work cell may comprise unitsassisting with the pipetting, dosing, mixing of samples and/or reagents.The work cell may comprise a reagent holding unit for holding reagentsto perform the assays. Reagents may be arranged for example in the formof containers or cassettes containing individual reagents or group ofreagents, placed in appropriate receptacles or positions within astorage compartment or conveyor. It may comprise a reaction vessel orcuvette feeding unit. It may comprise one or more liquid processingunits, such as a pipetting unit, to deliver samples and/or reagents tothe reaction vessels. The pipetting unit may comprise a reusablewashable needle, e.g. a steel needle, or disposable pipette tips. Thework cell may further comprise one or more mixing units, comprising e.g.a shaker to shake a cuvette comprising a liquid or a mixing paddle tomix liquids in a cuvette or reagent container.

A pre-analytical work cell can be either a stand-alone apparatus ormodule within a larger instrument assisting users with the sortingand/or preparation of samples before being processed by an analyticalwork cell. It may comprise for example one or more of the following: aresorting unit to sort samples according to type of analysis and/orpriority of analysis, a centrifuge for centrifugating sample tubes, analiquoting unit wherein a pipetting unit is used to aliquot samples fromsample tubes, a thermal treatment unit to subject the sample to acertain temperature, a separation unit to separate sample components,etc.

A post-analytical work cell can be either a stand-alone apparatus ormodule within a larger instrument assisting users with the storingand/or disposal of samples after being processed by an analytical workcell. It may comprise for example a resorting unit to resort sampletubes, e.g. to different storage racks, and/or a refrigeratedcompartment.

In general, a work cell may comprise units for loading and/or unloadingand/or transporting and/or storing sample tubes or racks comprisingsample tubes, units for loading and/or unloading and/or transportingand/or storing reagent containers or cassettes, units for loading and/orunloading and/or transporting and/or storing and/or washing reactioncontainers, e.g. cuvettes. The reaction containers may be disposable,i.e. single use, or reusable, i.e. adapted to be washed and reused. Itmay comprise identification units comprising sensors, e.g. barcode orRFID readers. A work cell may also comprise one or more incubation unitsfor maintaining sample/reagent mixtures at a certain temperature duringreaction, wash stations for washing pipette tips or needles, mixingpaddles, etc.

As each work cell may be designed for processing a certain number ofsamples or sample tubes per time unit, and this number may vary, thesystem may be advantageously set up such that the number of closureholders and/or the number of actuators and/or the number of tubegrippers and/or the number of pipetting units is adapted to thethroughput of each work cell.

Also, as each work cell may process only or preferably either sampletubes on single carriers or on racks carrying a plurality of tubes, eachdecapping/recapping device may advantageously process sample tubestransported on either single tube carriers and/or racks carrying aplurality of sample tubes.

According to one embodiment, the system can comprise a transportationunit for automatically transporting sample tubes from one work cell toanother work cell. The transportation unit may also transport singlecarriers or tube racks or both. The transportation unit may comprisee.g. one or more transport lines arranged e.g. as transport bands orguide rails. The transportation unit may be connected to, e.g. be anextension of, the tube conveyor of various decapping/recapping devices.Bypass lines and/or junctions may also be present so that specificwork-cells may be accessed in a random-access manner, by delivering theright sample to the right work-cell at the right time, according to needor priority and/or according to the type of tube or tube carrier, andnot necessarily sequentially. The transportation unit may alternativelycomprise a series of autonomous robotic carriers with random access toany work cell.

Alternatively, sample tubes and/or tube carriers may be transported fromone work cell to another work cell manually by the user.

Referring initially to FIG. 1, FIG. 1 a shows a pipetting system 200 forwithdrawing volumes of samples from sample tubes 12 and/or dispensingvolumes of liquid into sample tubes 12 according to one embodiment. Thepipetting system 200 can comprise a decapping/recapping device 100 (moreclearly illustrated in FIG. 1 b), for removing closures 11 of variabletype 11′, 11″ from sample tubes 12 of variable type 12′, 12″, and forreclosing the same tubes 12′, 12″ with the same respective closures 11′,11″. The decapping/recapping device 100 can comprise six individualclosure holders 20 arranged symmetrically on a rotatable carousel 61,having a respective number of arms 62, and each arm receiving oneclosure holder 20. Each closure holder can comprise a passive closuregripper 21 for holding a closure 11. The device 100 can further comprisethree actuators 40 and, in particular, a decapping actuator 40′ foractuating the passive closure grippers 21 when removing a closure 11from a tube 12, a recapping actuator 40″ for reclosing the tube 12 withits respective closure 11, and a waste actuator 40′″ for eventuallyreleasing a closure 11 into a waste compartment (not shown). The device100 can further comprise two tube grippers 50. In particular, a fixeddecapping station comprising a decapping tube gripper 50′ aligned withthe decapping actuator 40′ and cooperating with the decapping actuator40′ for biasing a tube 12 and its closure 11 away from each other whenremoving the closure 11. A fixed recapping station comprising arecapping tube gripper 50″ aligned with the recapping actuator 40″ andcooperating with the recapping actuator 40″ for biasing the tube 12 andits closure 11 towards each other when reclosing the tube 12. Thedecapping actuator 40′ can be coupled to a passive closure gripper 21 ofa closure holder 20 when a closure 11 is removed from a tube 12. Therecapping actuator 40″ can be coupled to a passive closure gripper 21 ofa closure holder 20 when a tube 12 is reclosed with its respectiveclosure 11. The waste actuator 40′″ can be coupled to a passive closuregripper 21 of a closure holder 20 when a closure is disposed. Anactuator 40 can be decoupled from a passive closure gripper 21 when theclosure holder 20 is holding a closure 11.

The pipetting system 200 can further comprise a pipetting unit 150synchronized with the decapping/recapping device 100 to withdraw avolume of sample from an opened sample tube or dispense a volume ofliquid into the sample tube 12 in the time frame between the opening ofa tube 12 and the reclosing of the tube 12 with the same closure 11.

FIGS. 2 a-d illustrate the structure of a closure holder 20 and theworking mechanism of a passive closure gripper 21, according to oneembodiment. In particular, FIG. 2 a shows the closure holder 20 fromoutside. FIG. 2 b shows the inside of the passive closure gripper 21 inits passive mode. FIG. 2 c shows the inside of the passive closuregripper 21 when it is activated. FIG. 2 d shows a bottom view of theclosure holder 20 in its passive mode. The closure holder 20 can have asymmetrical construction comprising an upper coupling part 22 coupled toan actuator 40 and a lower cylindrical part 23 comprising a cavity 36for receiving a closure 11 (closure not shown). The passive closuregripper 21 can comprise three cantilever arms 28 pivotable abouthorizontal fulcrum elements 38 and symmetrically arranged with respectto a central vertical axis 37 of the closure holder 20. Each cantileverarm 28 can comprise a jaw 27 mounted at the lower end and a wheel 30mounted at the upper end. A cantilever spring 29 can be also mounted onone side of each cantilever arm 28 for exercising a force on thecantilever arm 28 such as the lower end and therefore the jaw 27 can bepushed towards the outside of the lower part 23 of the closure holder 20in absence of other forces.

The passive closure gripper 21 can further comprise a pre-tensioningmember comprising a passive element 31 and a coil spring 32 andsymmetrical arranged with respect to the axis 37. The passive element 31can comprise a pin protruding out of the coupling part 22 of the closureholder 20 along axis 37 and a lower conical part providing a surface ofcontact with the coil spring 32 at the bottom and with the wheels 30 onthe side. The force applied by the coil spring 32 to the passive element31 and therefore the force applied by the passive element 31 to thethree cantilever arms 28 can be greater than the sum of the forcesapplied by the three cantilever springs 29 to the three cantilever arms28. Thus, the force of the coil spring 32 prevails pushing the passiveelement 31 upwards and the wheeled ends of the cantilever arms outwards,i.e. the jawed ends of the cantilever arms 28 are pushed inwards againstthe force of the cantilever springs 29, which tend to push them outwards(FIG. 2 b). Each jaw 27 can comprise two surfaces facing the inside ofthe closure holder 20, and forming an angle of substantially 120°. Thethree jaws 27 thus form a regular geometrical gripping surface (FIG. 2d) which enables a more efficient grip and prevents asymmetricaldeformations of the closure 11. Further each jaw 27 can comprise aseries of conical protrusions 35, which act as friction surface for aneven better grip, i.e. for preventing sliding or misplacement duringdecapping, recapping or holding of the closure 11, while reducing thepoints of contact. If a closure 11 (not shown in FIG. 2 a-2 d) islocated between the jaws 27, the pressure applied symmetrically to theoutside of the closure 11 is such that the closure 11 can be heldpassively in place. In addition, each jaw 27 can pivot about ahorizontal jaw axis 38′ and can thus be capable of varying its anglerelative to the central vertical axis 37 of the closure holder. This canenable the jaws to adapt to different inclinations of the sides of aclosure 11 without losing gripping surface and power.

Upon coupling with an actuator 40 (not shown in FIG. 2 a-2 d), a forcecan externally be applied to the passive element 31, which can begreater than the force of the coil spring 32. The passive element 31 cantherefore be pushed downwards allowing the wheeled part of thecantilever arms 28 to disengage. The only force acting on the cantileverarms 28 is at this point that of the cantilever springs 29, which thuspush the jawed ends of the cantilever arms 28 outwards (FIG. 2 c), henceopening the jaws 27 and releasing the pressure from a closure 11 inbetween or allowing a new closure 11 to be inserted between the openjaws 27 before they are closed again. The lower part 23 of the closureholder 20 can comprise an aperture 39 in correspondence to eachcantilever arm 28 through which the jawed end of the cantilever arm 28can extend when opening or when accommodating a closure 11 of largerdiameter.

The closure holder 20 can further comprise a passive closure pushelement 33 comprising a resilient member, i.e. a second coil spring 34,for exercising a push force on the closure 11 in a vertical directionwhen the passive pressure of the jaws 27 is released. The push element33 is shown in its relaxed position in FIG. 2 b and in its tensionedposition in FIG. 2 c. The resilient force of the resilient member can bechosen such that it is weaker than the resilient force of thepre-tensioning member. In this way, upon inserting a closure 11 betweenthe gripping tool, i.e. by lifting a closed sample tube 12 towards theclosure holder 20, the push element 33 can be pushed upwards by theclosure 11 and the second coil spring 34 can be tensioned. Therefore, aslong as the closure 11 remains tight between the jaws 27, during theholding period, the push element 33 is limited to exercise only apressure on the top of the closure 11. In the event that the closure 11has to be disposed, the push element 33 can provide a push impulse tothe closure 11 contributing to expel it downwards out of the closureholder 20 when opening the jaws 27. The push element 33 is further fitwith its bottom into a concave top of certain types of closure 11′, suchas to prevent asymmetrical deformation and/or tilting of the closure 11′when the jaws 27 apply a pressure on its sides, thus acting as astabilizer of the closure 11′.

FIG. 3 shows an actuator 40, such as the decapping actuator 40′ and therecapping actuator 40″ wherein some parts are removed for illustrativepurpose. The actuator 40, 40′, 40″ can comprise an active bolt 41connected to a spindle motor 46 for exercising a pressure on the passiveelement 31 of a passive closure gripper 21 when the actuator 40, 40′,40″ and the passive closure gripper 21 are in coupling connection, theforce applied by the active bolt 41 can be greater than the force of thefirst coil spring 32. Thus, the active bolt 41 acting on the passiveelement 31 can have the function to indirectly open the jaws 27, everytime a closure 11 needs to be gripped or released. The actuator 40, 40′,40″ can further comprise a closure-gripper drive comprising a couplingdisc 43 connected to a DC stepper motor 47 via drive belt 44 forrotating the closure holder 20 about its axis 37. The engagement betweencoupling disc 43 and coupling part 23 of the closure device 20 isdiscussed below with reference to FIGS. 6 a to 6 c.

In case of the waste actuator 40′″ (shown in FIG. 1 b), there isnormally no need for rotating the passive closure gripper 21 but only torelease the pressure applied to the closure 11 by opening the jaws 27.Therefore the waste actuator 40′″ can comprise the active bolt 41 but noclosure-gripper drive for rotating the passive closure gripper 21.

FIGS. 4 a and 4 b refer to closure-holder drive 60. The closure-holderdrive 60 can comprise a carousel 61 comprising six arms 62, eachcarrying one of the six closure holders 20 as illustrated in FIGS. 1 aand 1 b. The carousel 61 can be mounted on a rotor 63 connected to a DCstepper motor 65 via a belt 66 for being rotated about an axis 67 inorder to bring sequentially the closure holders 20 in couplingconnection with any of the actuators 40. The closure-holder drive 60 canfurther comprise a position sensor 68 assisting in determining theinitial correct position and for controlling/monitoring the angle ofrotation such as to facilitate a proper alignment between actuators 40and closure holders 20 at every rotation.

FIG. 4 b is a partially cut view of the carousel 61 of FIG. 4 a showinghow a closure holder 20 can be mounted on an arm 62 of the carousel 61.In particular, a disc 69 can be concentrically fixed around the couplingpart 22 of the closure holder 20. The disc 69 can then be sandwichedinto a chamber 64 of the arm 62 such as the lower part 23 of the closureholder 20 extends below the arm 62, the coupling part 22 of the closureholder 20 extends in part above the arm 62 and the whole closure holder20 comprising the disc 69 is rotatable about the axis 37 with respect tothe chamber 64.

FIG. 5 is a top view of the system 200 of FIG. 1 a wherein some partshave been removed for clarity. The actuators 40 can be fixed while thecarousel 61 is rotatable counterclockwise. Six closure holders 20numbered respectively 1 to 6 can be arranged symmetrically at intervalsof approximately 60° and at a distance from the center of the rotor 63,which can correspond to the distance of the active bolts 41 of theactuators 40 measured from the center of the rotor 63. The actuators 40can also be arranged with respect to each other so that coupling betweena passive closure gripper 21 and any actuator 40 is possible uponrotating the rotor 63 of regular steps, in this case 60° or multiples of60°. The device 100 can further comprise a tube conveyor, in this case,a linear conveyor 90 to transport tube racks 91, each carrying up to 5sample tubes 12. The distance between the decapping actuator 40′ and therecapping actuator 40″ can correspond to the distance between thecenters of six tubes 12, i.e. between two tubes 12 occupying the samerespective position on two adjacent racks 91. In this way, two tubes 12may be brought in alignment with two closure holders 20 and twoactuators 40 at the same time. The conveyor 90 can be being synchronizedwith the rotor 63 to advance the racks 91 stepwise such as a new tube 12and a new closure holder 20 are brought in alignment at the same timewith the same actuator 40, in this case either the decapping actuator40′ or the recapping actuator 40″. The decapping tube gripper 50′ andthe recapping tube gripper 50″ are also aligned with the decappingactuator 40′ and recapping actuator 40″ respectively. The decapping tubegripper 50′ can be synchronized with the conveyor 90 to lift a tube 12and with the rotor 63 to bring a free closure holder 20 in couplingconnection with the decapping actuator 40′ such as to remove a closure11 from that tube 12 at that position at that time. The recapping tubegripper 50″ can be synchronized with the conveyor 90 to lift a tube 12and with the rotor 63 to bring the same closure holder 20 holding theclosure 11 previously removed from that same tune 12 in couplingconnection with the recapping actuator 40″ such as to reclose that tube12 at that position at that time.

One possible workflow of the decapping/recapping device 100 according tothis embodiment is summarized in the following example. At start, allsix closure holders 20 can be free. The device 100 can be initialized,via position sensor 68 (not shown in FIG. 5), such as a closure holder20, e.g. closure holder 20, 1 is aligned with the decapping actuator40′. The conveyor 90 can then be instructed to advance the racks 91 suchthat as the first tube 12 on the first rack 91 is brought in alignmentwith the decapping actuator 40′ and therefore with the closure holder20, 1 and the decapping tube gripper 50′. The dacapping actuator 40′ iscoupled to the passive closure gripper 21 of closure holder 20,1 suchthat as the active bolt 41 applies a force on passive element 31 therebycausing the jaws 27 to be opened. The decapping tube gripper 50′ isinstructed to lift the tube 12 until the closure 11 is at a heightbetween the open jaws 27. In order to determine the height, account istaken of a measurement carried out by a sensor (not shown) during theadvancement of the rack 91 determining the type of tube 12 and/orclosure 11. The jaws 27 are then closed by releasing the pressure by theactive bolt 41. The decapping actuator 40′ is then instructed to rotatethe coupling disc 53 for rotating the passive closure gripper 21, whilethe decapping tube gripper 50′ is instructed to pull the tube 12downwards back on the rack, thereby cooperating with the decappingactuator 40′ to remove the closure 11 from the tube 12 via passiveclosure gripper 21 of closure holder 20, 1.

The rack 91 can then be advanced to another position, such as the nexttube 12 is brought into alignment with the decapping actuator 40′ andthe decapping tube gripper 50′. At the same time, the next closureholder 20, 6 is brought in alignment with the decapping actuator 40′ byrotating the rotor 63 of 60° counterclockwise and the procedure isrepeated. The closure holder 20, 1 has thus moved to 60°counterclockwise while holding passively the closure 11 removed from thefirst tube 12, the closure holder 20, 1 no longer being coupled to anyactuator 40.

Performing this step five times, five tubes 12 have been opened andrespective closures have been transported stepwise counterclockwise 60°at a time by respective passive closure holders 20, 1, 2, 3, 4, 5. Whenclosure holder 20, 6 comes into alignment with decapping actuator 40′,closure holder 20, 1 holding the first closure 11, comes into alignmentwith recapping actuator 40″. At the same time, while the 6^(th) tube 12,i.e. the first tube on the second rack 91, comes in alignment with thedecapping tube gripper 50′ and decapping actuator 40′, the first tube 12on the first rack 91, which was first opened, comes into alignment withthe recapping tube gripper 50″ and recapping actuator 40″, thereforewith closure holder 20, 1 holding its respective closure 11, i.e. thesame closure 11 removed from that same tube 12.

From this point on, the decapping station 70 and recapping station 80will work in the same time frame, each performing its respective task ofdecapping and recapping. In particular, nearly the same steps of thosecarried out at the decapping station 70 occur at the recapping station80 but in reverse order. Specifically, at the recapping station 80, therecapping actuator 40″ is instructed to rotate the coupling disc 43 forrotating the passive closure gripper 21 in the opposite direction, whilethe recapping tube gripper 50′ is instructed to lift the tube 12 upwardstowards the closure 11, using the same information on the type of tubealready acquired, thereby cooperating with the decapping actuator 40′ toreclose the tube 12 with the same closure 11 via passive closure gripper21 of closure holder 20,1. It is to be noted that the angular positionof the closure 11 with respect to the tube 12 is different at thedecapping station 70 and the recapping station 80 respectively. This isdue to the fact that the tube 12 has been transported linearly from thedacapping station 70 to the recapping station 80 without rotating onitself. On the other hand, the closure holder 20,1 has been transportedwith a rotational movement of the rotor 63 of 300° counterclockwise fromthe decapping station 70 to the recapping station 80. There is thereforea difference of −60° in the angular position of the closure 11 withrespect to the tube 12 at the recapping station 80 compared to thedecapping station 70. This difference may have an influence on theproper closing of a tube 12, especially if the closure 11 is of thescrew type. In order to take account of this difference, the recappingactuator 40″ is instructed to rotate the coupling disc 43 for rotatingthe passive closure gripper 21 of an additional 60°. The active bolt 41applies then a force on passive element 31 thereby causing the jaws 27to be opened and the recapping tube gripper 50″ is instructed to lowerthe tube 12 on the rack 91. The recapping actuator 40″ is thus decoupledfrom the closure holder 20, 1, which is again free to return to thedecapping station 70 for receiving a new closure and starting a newcycle.

The pipetting unit 150 can be synchronized with the decapping/recappingdevice 100 to withdraw a volume of sample and/or dispense a volume ofliquid in the time frame between the opening of a tube 12 and thereclosing of the tube 12 with the same closure 11. In particular, thepipetting unit 150 can be temporarily lowered such as a needle (notshown in FIG. 5) is dipped into a sample via the open end of a tube 12when the tube 12 is at an intermediate position between the decappingstation 70 and the recapping station 80 and during the time frame inwhich the decapping station 70 and/or the recapping station 80 areoperating with other respective tubes and the rotor 63 is not rotating.Optionally a pipetting tube gripper (not shown) may be employed to liftthe open tube 12 and facilitate the pipetting operation by shorteningthe distance of travel of the pipetting unit 150.

FIGS. 6 a and 6 b show in perspective from top and bottom respectivelyhow an actuator 40, in particular a decapping actuator 40′ and recappingactuator 40″ can be engaged with a passive closure gripper 21 (someparts removed for clarity). In particular, the coupling part 23 of theclosure holder 20 can comprise two pins 26 on its upper surface locatedon opposite sides of the passive element 31 located at the center. Thepassive element 31 can lay out of the line between the two pins 26 sothat when the closure holder 20 is mounted on an arm 62 of the carousel61, the passive element 31 and the two pins 26 can lay on a an imaginarycircle having as radius the distance between the center of the passiveelement 31 and the center of the rotor 63. The coupling disc 43 cancomprise on the bottom a groove 45 having a width and a depth largeenough to allow the pins 26 and the passive element 31 to fit in.Additional the groove 45 can have a curvature corresponding to that ofan imaginary circle having as radius the distance between the center ofthe active bolt 41 and the center of the rotor 63 such as the pins 26and the passive element 31 can pass smoothly through when the carousel61 is rotated. Engagement can be complete when the passive element 31and the active bolt 41 are in alignment. The active bolt 41 can beextendable and retractable through a hole in the center of the groove45.

Each arm 62 can comprise alignment device, such as a magnet 27 toattract a ferromagnetic element 28 located on one side of the couplingpart 23 of each closure holder 20.

Each magnet 27 and each ferromagnetic element 28 can be located suchthat when the closure holder 20 is decoupled from an actuator 40, due tothe magnetic force exercised by the magnet 27 on the ferromagneticelement 28, rotation of the closure element 20 about its axis 37 isprevented and the same angular position of the closure holder 20 withrespect to its respective arm 62 is maintained during rotation of therotor 63. Each magnet 27 and each ferromagnetic element 28 can belocated such that the pins 26 of the closure holder 20 are aligned withgroove 45 when a closure holder 20 is be coupled to an actuator 40. Whenthe closure holder 20 is coupled to a decapping actuator 40′ orrecapping actuator 40″ the coupling disc 43 can apply a rotational forceto the closure holder 20 via groove 45 acting on the pins 26, which canbe greater than the magnetic force, thereby causing rotation of theclosure holder 20 about its axis 37.

FIG. 6 c shows the actuator 40 and passive closure gripper 21 alreadyengaged (some parts removed for clarity). The pins 26 and passiveelement 31 can be inside the grove 45. The active bolt 41 can be alignedwith the passive element 31. In addition, the active bolt 41 is shownwhile applying a force to the passive element 31 thereby establishing afirst coupling connection between the actuator 40 and the passiveclosure gripper 21. Upon rotation of the coupling disc 43, a rotationalforce can also be applied to the closure holder 20, thereby establishinga second coupling connection. A coupling connection can occur at thetime when a force is transferred from the actuator 40 to the closureholder 20 or passive closure gripper 21. A closure holder 20 may beengaged, i.e. aligned with an actuator 40 without coupling taking placeif not necessary. This is the case for example with the waste actuator40′″. Moreover, engagement with the waste actuator 40′″ can compriseonly alignment between the active bolt 41 and passive element 31. Also,coupling can comprise only a transfer of force from the active bolt 41to the passive element 31.

FIG. 7 shows a tube gripper 50 in detail. The tube gripper 50 cancomprise a first tube gripping tool 51 comprising two upper tubegripping jaws 51′, 51″ mounted on two respective first tube grippingarms 55′ and 55″, biasable with respect to each other. The tube gripper50 can further comprise a second tube gripping tool 52 comprising twolower tube gripper jaws 52′ and 52″ mounted on two respective secondtube gripping arms 54′ and 54″, biasable with respect to each other andin the same direction as the upper tube gripping jaws 51′, 51″. Inaddition, first tube gripping arms 55′ and 55″ can be mounted on secondtube gripping arms 54′ and 54″ respectively and are biasable withrespect to second tube gripping arms 54′ and 54″ via a resilient device53. Upper tube gripping jaws 51′, 51″ and lower tube gripping jaws 52′and 52″ each can comprise a gripping surface for gripping a tube fromopposite sides respectively, wherein the upper tube gripping jaws 51′,51″ are longer than the lower tube gripping jaws 52′ and 52″ and thegripping surface of the upper tube gripping jaws 51′, 51″ can be smallerthat the gripping surface of the lower tube gripping jaws 52′ and 52″.The tube gripper 50 can further comprise a first DC stepper motor 56connected via spindle drive 57 to second tube gripping arms 54′ and 54″for biasing the second gripping arms 54′ and 54″ and therefore lowertube gripping jaws 52′ and 52″ towards each other when gripping a tube12 and away from each other when releasing a tube 12. Since first tubegripping arms 55′ and 55″ are mounted on second tube gripping arms 54′and 54″, they can also be biased accordingly. The tube gripper 50 canfurther comprise a second DC stepper motor 58 for lifting and loweringsecond tube gripping arms 54′ and 54″ and together first tube grippingarms 55′ and 55″. Since upper tube gripping jaws 51′ and 51″ are longerthan lower tube gripping jaws 52′ and 52″ and biasable with respect toeach other via resilient means 53, the tube gripper 50 may be set up viamotors 56 and 58 such that the upper tube gripping jaws 51′ and 51″ cangrip and lift a tube from a tube carrier before the lower tube grippingjaws 52′ and 52″ can grip and hold securely a tube with a force and asurface of contact which can be greater than the force and surface ofcontact of the upper tube gripping jaws 51′, 51″ respectively.Analogously, the tube gripper 50 may be set up such that the lower tubegripping jaws 52′ and 52″ can release the tube before the upper tubegripping jaws 51′ and 51″ when lowering the tube back on the tubecarrier.

FIG. 8 a shows a perspective view of a decapping/recapping device 300according to another embodiment. The difference with thedecapping/recapping device 100 of FIG. 1 b and FIG. 5 is that itoperates with single tube carriers 391 transported by conveyor 390. Inparticular, the decapping/recapping device 300 can comprise a fixeddecapping actuator 340′ and a decapping tube gripper 350, 350′ alignedat a decapping station 370, a recapping actuator 340″ and a recappingtube gripper 350, 350″ aligned at a recapping station 380, a wasteactuator 340′″ and a waste well 384 aligned with a waste compartment(not shown) at a waste station 385. Three closure holders 20 can bearranged symmetrically at intervals of about 120° on three respectivearms 362 of a carousel 361, which can rotate counterclockwise via rotor363. The decapping station 370, the recapping station 380 and the wastestation 385 can also be arranged with respect to each other so thatcoupling between a passive closure gripper 21 and any actuator 340 ispossible upon rotating the rotor 363 of regular steps of about 120° ormultiples of about 120°. The device 300 can further comprise a tubeconveyor, in this case a linear conveyor 390 to transport pucks 391,each carrying a single tube 12. The distance between the decappingstation 370 and the recapping station 380 can correspond to the distancebetween the centers of a first and third tube in a series of three tubes12 carried by respective pucks 391 adjacent to each other. In this way,two tubes 12 may be brought in alignment with two closure holders 20 andtwo actuators 340′, 340″ at the same time. The workflow of thisembodiment may be analogous to that described with reference to FIG. 5,except that a cycle can be completed every three tubes instead of sixand the steps of rotation are of 120° instead of 60°.

FIG. 8 b shows a pipetting system 400 comprising the decapping/recappingdevice 300 of FIG. 8 a. The pipetting system 400 can further comprise apipetting unit 250 synchronized with the decapping/recapping device 300to withdraw a volume of sample and/or dispense a volume of liquid in thetime frame between the opening of a tube 12 and the reclosing of thetube 12 with the same closure 11. In particular, the pipetting unit 250can be temporarily lowered so that a needle 251 can be dipped into asample via the open end of a tube 12 when the tube 12 is at anintermediate position between the decapping station 370 and therecapping station 380 and during the time frame in which the decappingstation 370 and/or the recapping station 380 are operating with otherrespective tubes and the rotor 63 is not rotating. Optionally apipetting tube gripper (not shown) may be employed to lift the open tube12 and facilitate the pipetting operation by shortening the distance oftravel of the pipetting unit 250 and/or of the pipetting needle 251.

FIG. 8 c shows the same pipetting system 400 of FIG. 8 b from anotherperspective. In particular the waste station 385 is more clearly shown,comprising a waste well 384 for guiding closures to be disposed into awaste compartment (not shown).

FIG. 8 d shows a top view of the same pipetting system 400 of FIGS. 8 band 8 c for better appreciating the difference with FIG. 5.

FIG. 9 shows more schematically a top view of a decapping/recappingdevice 500 according to another embodiment, in operation with tube racks91. The difference with the previous embodiments is that carousel 561can have the shape of a ring and can accommodate a larger number ofclosure holders 20, in this case twenty. Further, only a decappingstation 570 and recapping station 580 are shown, which can be arrangeddiametrically opposite with respect to the carousel 561. A cycle is inthis case can complete every eleven tubes 12. It can be also noted thata pipetting tube gripper 550′″ can be arranged at the center of thedevice 500 to lift one of the opened tubes 12 when the tube 12 passes atthat position and to facilitate the pipetting operation by shorteningthe distance of travel of the pipetting unit (not shown).

FIG. 10 shows schematically only one example of a system 900 forprocessing sample tubes. The system 900 can comprise a plurality of workcells 901-909. In particular, the system 900 can comprise apre-analytical work cell 901, a post-analytical work-cell 909, aplurality of analytical work-cells 902-906 to process sample tubes onsingle carriers and two analytical work-cells 907,908 to process sampletubes on tube racks. The system 900 can further comprise atransportation unit 920 to transport sample tubes on both singlecarriers and tube racks from one work cell to any other work cellaccording to the need. The system 900 can further comprise a pipettingsystem 911-918 in correspondence to each work cell 901-908 respectively,for withdrawing a volume of sample from a sample tube to be processed bythe work cell 901-908. The pipetting system 911-918 can comprise adecapping/recapping device for removing a closure from a sample tubewhen a sample needs to be withdrawn and for reclosing the sample tubebefore it is transported by the transportation unit 920 to another workcell 901-909.

A decapping or decapping and recapping device can comprise a pluralityof individual passive closure holders each comprising a passive closuregripper, and at least one actuator for actuating the passive closuregripper when removing a closure or reclosing a tube. One actuator can becoupled to one passive closure gripper when a closure has to be removedfrom a tube or when a closure has to be released from the closuregripper and can be decoupled from a passive closure gripper when theclosure holder is holding a closure. This can increase processingthroughput without the need to use additional closures and withoutsevere limitations on processing steps. In this way also cost savingscan be obtained by avoiding the use of additional closures and by areduced complexity of the device.

Another advantage can be that the device enables to process sample tubesof variable shape and with closures of variable shape. This can enablethe processing of primary tubes as well as secondary tubes.

Another advantage can be the risk of cross-contamination can beminimized.

Another advantage can be the throughput can also be increased even ifthe device is used as a decapping device only.

Another advantage can be that sample processing throughput in a systemcomprising a plurality of work-cells can be optimized. This can beachieved by having a decapping/recapping device for each work cell forremoving a closure from a primary tube when and where a sample needs tobe withdrawn and for reclosing the primary tube before it is transportedto another work cell.

An advantage can be that tubes may be transported closed by a closurewithin the system, that is from one work-cell to another and opened onlywhen and where needed. In this way the risk of spilling samples out ofthe tubes, the risk of cross-contamination, evaporation and thebio-hazard risk can be minimized.

Using a decapping/recapping device can enable the adaptation of thethroughput of decapping and recapping of sample tubes to the sampleprocessing throughput and the specific workflow of each work cellwithout depending by the throughput of a central or commondecapping/recapping device. It can also be possible to adapt thedecapping/recapping device to the type of sample tube carrier requiredby each work cell, which may differ from one another, e.g. single tubecarrier or rack for carrying a plurality of sample tubes.

It should be clear that the above are just examples of some embodimentsand that variations are possible according to the particular needwithout departing from the scope of the disclosure. In particular, adecapping/recapping device may be designed to operate with both singletube carriers and tube racks, wherein tube racks may carry a differentnumber of tubes. Also, a different combination of the number of closureholders and actuators as well as a different arrangement may beconceived. Especially, a different coupling mechanism may be conceived.

It is noted that terms like “preferably,” “commonly,” and “typically”are not utilized herein to limit the scope of the claimed embodiments orto imply that certain features are critical, essential, or evenimportant to the structure or function of the claimed embodiments.Rather, these terms are merely intended to highlight alternative oradditional features that may or may not be utilized in a particularembodiment of the present disclosure.

For the purposes of describing and defining the present disclosure, itis noted that the term “substantially” is utilized herein to representthe inherent degree of uncertainty that may be attributed to anyquantitative comparison, value, measurement, or other representation.The term “substantially” is also utilized herein to represent the degreeby which a quantitative representation may vary from a stated referencewithout resulting in a change in the basic function of the subjectmatter at issue.

Having described the present disclosure in detail and by reference tospecific embodiments thereof, it will be apparent that modifications andvariations are possible without departing from the scope of thedisclosure defined in the appended claims. More specifically, althoughsome aspects of the present disclosure are identified herein aspreferred or particularly advantageous, it is contemplated that thepresent disclosure is not necessarily limited to these preferred aspectsof the disclosure.

1. A decapping device for removing closures from sample tubes, thedecapping device comprising: a plurality of individual closure holders,each individual closure holder comprising a passive closure gripper forholding a closure; at least one actuator for actuating the passiveclosure gripper when removing a closure from a tube or releasing aclosure, wherein the at least one actuator is coupled to the passiveclosure gripper of an individual closure holder when removing a closurefrom a tube or when releasing a closure and is decoupled from thepassive closure gripper when the individual closure holder is holding aclosure; and at least one tube gripper cooperating with the at least oneactuator for biasing a tube and its closure away from each other whenremoving the closure.
 2. The decapping device according to claim 1,wherein the passive closure gripper comprises a plurality of jaws,wherein the plurality of jaws comprise protrusions and cooperate witheach other to grip and hold a closure.
 3. The decapping device accordingto claim 2, wherein each jaw is pivotable about a horizontal jaw axis byvarying its angle relative to the central vertical axis of the closureholder such as to adapt to different inclinations of the sides of theclosure
 4. A decapping/recapping device for removing closures fromsample tubes and for reclosing the sample tubes with the same respectiveclosures, the decapping/recapping device comprising: a plurality ofindividual closure holders, each individual closure comprising a passiveclosure gripper for holding a closure; at least one actuator foractuating the passive closure gripper when removing a closure from atube or reclosing a tube with its respective closure, wherein the atleast one actuator is coupled to the passive closure gripper of anindividual closure holder when removing a closure from a tube or whenreclosing a tube with its respective closure and is decoupled from thepassive closure gripper when the individual closure holder is holding aclosure; and at least one tube gripper cooperating with the at least oneactuator for biasing a tube and its closure away from each other whenremoving the closure and for biasing the tube and its closure towardseach other when reclosing the tube.
 5. The decapping/recapping deviceaccording to claim 4, wherein the passive closure gripper comprises aplurality of jaws,
 6. The decapping/recapping device according to claim5, wherein the plurality of jaws comprise protrusions and cooperate witheach other to grip and hold a closure.
 7. The decapping/recapping deviceaccording to claim 4, wherein the closure holder comprises a passiveclosure push element.
 8. The decapping/recapping device according toclaim 4, wherein the closure gripper is rotatable about a centralvertical axis of the closure holder upon coupling the actuator to thepassive closure gripper, wherein the actuator comprises aclosure-gripper drive for rotating the closure gripper.
 9. Thedecapping/recapping device according to claim 4, further comprising, aclosure-holder drive for sequentially and/or repeatedly bringing theplurality of individual closure holders in coupling connection with oneor more actuators.
 10. The decapping/recapping device according to claim4, further comprising, a decapping station having a decapping actuatoraligned to a decapping tube gripper; and a recapping station having arecapping actuator aligned to a recapping tube gripper, wherein aclosure holder and a sample tube are movable from the decapping station,the decapping actuator and the decapping tube gripper cooperate with thepassive closure gripper to remove a closure from the sample tube, to therecapping station wherein the recapping actuator and the recapping tubegripper cooperate with the passive closure gripper holding the closureto reclose the sample tube with the same closure.
 11. Thedecapping/recapping device according to claim 4, further comprising, aheight determining detector cooperating with the tube gripper fordetermining a height at which a sample tube is to be lifted whenremoving a closure from the sample tube or reclosing the sample tubewith its closure.
 12. The decapping/recapping device according to claim4, wherein the tube gripper comprises a first tube gripping tool and asecond tube gripping tool, wherein the first tube gripping tool isbiasable with respect to the second tube gripping tool and cooperateswith the second tube gripping tool such that the first tube grippingtool grips and lifts a sample tube from a tube carrier before the secondtube gripping tool grips and holds securely the sample tube with a forceand a surface of contact greater than the force and surface of contactof the first tube gripping tool respectively.
 13. Thedecapping/recapping device according to claim 4, further comprising, anerror detector to determine whether a closure has been removed and/or asample tube has been reclosed with its respective closure and/or toprevent that a sample tube is reclosed with a non-respective closure.14. The decapping/recapping device according to claim 4, furthercomprising, a waste station having a waste actuator aligned to a wastecompartment, wherein the waste actuator cooperates with the closuregripper holding the closure to dispose the closure into the wastecompartment.
 15. A pipetting system for withdrawing volumes of samplesfrom sample tubes and/or dispensing volume of liquids to sample tubes,the pipetting system comprising: a decapping/recapping device accordingto claim 4; and a pipetting unit adapted to withdraw a volume of sampleand/or dispense a volume of liquid in the time frame between removal ofa closure from a sample tube and the reclosing of the sample tube withthe same closure.
 16. An analytical system for determining at least onesample parameter of a sample contained in a sample tube, the analyticalsystem comprising: a decapping/recapping device according to claim 4;and an analytical unit for determining the at least one sample parameterin the time frame between removal of a closure from a sample tube andthe reclosing of the sample tube with the same closure.
 17. A system forprocessing sample tubes comprising biological samples, the systemcomprising: a plurality of work cells for processing samples; apipetting system according to claim 15 in correspondence to at least onework cell for withdrawing a volume of sample from a sample tube to beprocessed by the work cell and/or for dispensing a volume of liquid intoa sample tube, for removing a closure from a sample tube when a sampleneeds to be withdrawn and/or a liquid needs to be dispensed and forreclosing the sample tube before it is transported to another work cell.